Abstract：
Zhuzhou was one of the most polluted cities in China with the serious acid rain. Due to the implementation of air pollution control measures from 2016 to 2018, the acid rain pollution in this city has reduced. In order to understand the recent situation, a comprehensive study on the acid rain was carried out from January 2011 to December 2020. The pH values during the study period varied from 3.3 to 7.5, with a volume-weighted mean value of 4.7. The predominant acidic components of the precipitation were SO42- and NO3-, accounting for 89.3% of the total anions. The ratio of non-sea-salt SO42- to NO3- showed a decreasing trend, revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound type. The correlation analysis (p < 0.05) showed that SO42- was positively correlated with NH4+, Ca2+, and Mg2+; hence, it predominated in precipitation as (NH4)2SO4, NH4HSO4, CaSO4, and MgSO4. Significant positive correlation of Ca2+ with Mg2+ shows that they may originated mainly from crust. Significant positive correlation between SO42- and F- and Cl- indicate that their source may be related to the non-ferrous metal smelting industry in Zhuzhou. Further correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO42- and F- in precipitation, while Cl- may still be emitted from other anthropogenic sources.
摘要：
株洲是中国污染最严重的城市之一，酸雨严重。由于2016年至2018年大气污染治理措施的实施,本市酸雨污染有所减轻。为了了解最近的情况，2011年1月至2020年12月对酸雨进行了全面研究。研究期间的pH值从3.3变化到7.5,体积加权平均值为4.7。沉淀的主要酸性成分是SO42-和NO3-，占总阴离子的89.3%。非海盐SO42-与NO3-的比值呈下降趋势,揭示了酸雨的污染类型从硫酸型转变为硫酸和硝酸复合型。相关性分析(p<0.05)显示SO42-与NH4+呈正相关,Ca2+,和Mg2+；因此，它以（NH4）2SO4，NH4HSO4，CaSO4和MgSO4的沉淀为主。Ca2与Mg2的显着正相关表明它们可能主要来自地壳。SO42-与F-、Cl-显著正相关,说明其来源可能与株洲有色金属冶炼行业有关。进一步的相关性分析表明,该地区有色金属冶炼行业的排放对SO42-和F-在降水中,而Cl-仍可能来自其他人为来源。
